Graded Weight-Bearing Exercise for Improving Ambulation after Stroke

Investigators: Charles G. Burgar, MD; Steven A. Kautz, PhD; and David A. Brown, PhD, PT

Project Staff: Christine A. Dairaghi, BS; Betty S. Troy, MS; Julie Harvey, MS; Cheryl D. Pierson-Carey, MS PT; Robert T. Whalen, PhD; and M. Elise Johanson, MS, PT

Summary: Persons with post-stroke hemiplegia need to improve lower limb function. Current therapy is clinician and patient intensive, and involves one joint or a single limb at a time. We have developed a new exercise regime for persons with hemiplegia. The exercise is performed by pedaling an ergometer, but instead of sitting on a bicycle seat, the patient stands safely in the pedals and is partially supported by a backboard, whose tilt determines the amount of weight that must be supported by the legs. The objective of this project is to perform clinical tests to show improved lower limb strength, improved weight-bearing capability, and improved functional ambulation in a group of chronic hemiplegic subjects who pedal the ergometer compared with subjects who undergo conventional therapeutic exercise.

Description: Exercise programs for muscle strengthening may be prescribed for people who have had a stroke. The effectiveness of a strengthening program for improving one's ability to walk after a stroke is a subject of debate in the rehab community. Preliminary evidence, from pilot studies in our lab, strongly suggests that a strengthening program is indeed effective. For people who have had strokes, muscle strengthening is an important component of a comprehensive exercise program aimed at restoring functional movement. However, the effect of these exercises on leg function has yet to be established.

The Tiltcycle is a device which helps patients improve their strength and coordination. By watching a computer display, the force generated by each pedaling leg can be seen. This information assists patients attempting to get both legs pedaling with the same force.

Problem: A stroke can leave a person with weakness, immobility, incoordination and decreased weight-bering capability on the weaker leg.

Approach: One form of dynamic exercise that can improve rehabilitation is pedaling, especially when used with performance feedback. The Tiltcycle is a modified, instrumented ergometer that provides the therapeutic benefits of pedaling as well as an effective means of movement assessment. The exercise involves dynamic alternating leg movements with the amount of weight-bearing and/or resistance graded according to the patient's level of recovery.

Funding Source: VA RR&D Merit Review

Related Work: Neural Constraints in Muscle Coordination of Pedaling